Strategies for valorisation of wastes from bioethanol production - PowerPoint PPT Presentation

CYPRUS 2016 4th International Conference on Sustainable Solid Waste Management Strategies for valorisation of wastes from bioethanol production – lactic acid and probiotics as added value products A. Djukić-Vuković 1 * , D. Mladenović 1 , J. Pejin 2 , L. Mojović 1 1 Faculty of Technology and Metallurgy, University of Belgrade 2 Faculty of Technology, University of Novi Sad *adjukic@tmf.bg.ac.rs

4th International Conference on Sustainable Solid Waste Management, Limassol , Cyprus, 23-25 June 2016 Strategies for valorisation of wastes from bioethanol production Stillage is a by ‐ product of bioethanol production on different substrates (corn, triticale, waste bread...).  What about advanced bioethanol – bioethanol produced on wastes and residues ? to 0.5% - advanced biofuels is target - EU Indirect land use change directive (April 2015)  Competitiveness of bioethanol as a alternative fuel is dependent on the environmentally friendly and economically feasible management of residues remaining after production process

4th International Conference on Sustainable Solid Waste Management, Limassol , Cyprus, 23-25 June 2016 Strategies for valorisation of wastes from bioethanol production Why lactic acid? Lactic acid (2-hydroxypropanoic acid) is widely used chemical in food, pharmaceutical and chemical industry – 7% annual growth rate. High demand for lactic acid is driven by increased production of polylactides (PLA, PLGA) - biocompatible polymers used for medical, pharmaceutical and food industry purposes. Specially attractive – LA for PLA produced from renewable sources. Fermentation enables selective production of L or D isomer. WHO: Probiotics are microorganism with beneficial effect on health of host – human or animal → 10

4th International Conference on Sustainable Solid Waste Management, Limassol , Cyprus, 23-25 June 2016 Strategies for valorisation of wastes from bioethanol production Aim: Lactic acid production on thin stillage Fermentation media sterilized liquid wasted bread, liquid molasses stillage and liquid corn stillage from bioethanol plant Reahem and Alpis, Serbia, initial sugar concentration was set at approximately 25 g/L Table 1. Chemical composition of different stillages Thin corn Thin molasses Thin wasted bread stillage stillage stillage Reducing carbohydrates (g L -1 ) 13.12 ± 0.70 4.20 ± 0.19 11.66 ± 0.68 Crude protein (g L -1 ) 8.42 ± 0.71 18.80 ± 0.61 21.00 ± 1.10 Ash (g L -1 ) 2.90 ± 0.32 17.60 ± 0.72 6.96 ± 0.23 Lipids (g L -1 ) 1.83 ± 0.45 0.80 ± 0.02 5.48 ± 0.81 Dry matter (%) 5.02 ± 0.29 6.61 ± 0.55 4.80 ± 0.48 Fermentation Batch, shaking of 90 rpm, 5% (v/v) inoculum concentration 41°C, microaerophylic, pH control: without and with addition of neutralizing agents (CaCO 3 , 30% NaOH in 4h intervals) Microorganism Lactobacillus rhamnosus ATCC 7469 – homofermentative, > 97% L(+)-lactic acid

4th International Conference on Sustainable Solid Waste Management, Limassol , Cyprus, 23-25 June 2016 Strategies for valorisation of wastes from bioethanol production thin wasted bread stillage 10.0 25 thin molassed stillage thin corn stillage 15 9.5 -1 ) 20 Lactic acid concentration (g L 9.0 log N (CFU mL -1 ) 10 8.5 15 8.0 5 10 7.5 7.0 0 5 0 12 24 36 Time (h) 0 12 24 36 Time (h) The highest LA concentration - thin wasted bread stillage

4th International Conference on Sustainable Solid Waste Management, Limassol , Cyprus, 23-25 June 2016 Strategies for valorisation of wastes from bioethanol production Table 2. LA fermentation parameters LA productivity (g L -1 LA concentration (g L -1 ) LA yield (g g -1 ) LA yield coefficient (g g -1 ) h -1 ) Thin corn stillage 13.24 ± 0.20 0.55 ± 0.02 0.89 ± 0.03 0.44 ± 0.02 Thin molasses stillage 13.41 ± 0.47 0.60 ± 0.03 0.98 ± 0.05 0.45 ± 0.02 Thin wasted bread 15.38 ± 0.27 0.69 ± 0.02 0.98 ± 0.03 0.51 ± 0.02 stillage CaCO 3 biomass 10 18 16 9 -1 ) 14 Lactic acid concentration (g L -1 ) 12 8 LogN (CFU mL 10 8 7 6 lactic acid 4 6 2 0 5 1% CaCO3 2% CaCO3 5% CaCO3 10% CaCO3

4th International Conference on Sustainable Solid Waste Management, Limassol , Cyprus, 23-25 June 2016 Strategies for valorisation of wastes from bioethanol production • Thin wasted bread stillage 20 18 • NaOH in 4h intervals -1 ) 16 Lactic acid concentration (g L 14 CaCO 3 12 LA yield → 0.77 g g -1 10 LA productivity → 1.14 g L -1 h -1 8 NaOH 6 Biomass → 8×10 9 CFU mL -1 4 2 0 L. rhamnosus ATCC 7469 has 0 12 24 36 48 60 Time (h) the probiotic characteristics!

4th International Conference on Sustainable Solid Waste Management, Limassol , Cyprus, 23-25 June 2016 Strategies for valorisation of wastes from bioethanol production WHOLE STILLAGE – HIGH GRAVITY STILLAGE (HGS) SEPARATION LACTIC ACID LA fermentation of HGS SOLID PART OF STILLAGE THIN STILLAGE (TS) FERMENTATION with free L. rhamnosus PROBIOTICS LA fermentation of TS DRYING SEPARATION with immobilized L. rhamnosus Crude fibres; 2,04% Hemicellulose FEED (DDG – DRIED Proteins, 4.01% Solid fraction of DESTILLER’S 40.24% Liquid fraction of SEPARATION fermentation media GRAINS ) fermentation with L. rhamnosus media with LA Feed for ATCC 7469 Solid fraction - L. Liquid fraction of biomass monogastric rhamnosus immobilized fermentation media with LA animals onto zeolite FEED WITH Lactic acid PROBIOTIC PROBIOTIC- ZEOLITE extraction Lactic acid Lipids; 4,92% BIOMASS Nitrogen-free ADDITIVE FOR FEED extraction extract, Ash; 0,35% 49.35% Process I Process II

4th International Conference on Sustainable Solid Waste Management, Limassol , Cyprus, 23-25 June 2016 Strategies for valorisation of wastes from bioethanol production Other possibilities ... WHOLE STILLAGE – HIGH GRAVITY STILLAGE (HGS) SEPARATION LA fermentation of HGS SOLID PART OF STILLAGE THIN STILLAGE (TS) with free L. rhamnosus LA fermentation of TS DRYING SEPARATION with immobilized L. rhamnosus FEED (DDG – DRIED Solid fraction of DESTILLER’S Liquid fraction of SEPARATION fermentation media GRAINS ) fermentation with L. rhamnosus media with LA ATCC 7469 Solid fraction - L. Liquid fraction of biomass rhamnosus immobilized fermentation media with LA onto zeolite FEED WITH Lactic acid PROBIOTIC extraction PROBIOTIC- ZEOLITE Lactic acid BIOMASS ADDITIVE FOR FEED extraction Process I Process II

4th International Conference on Sustainable Solid Waste Management, Limassol , Cyprus, 23-25 June 2016 Strategies for valorisation of wastes from bioethanol production Conclusions • Stillages from advanced bioethanol production have shown same or better characteristics than stillage from 1 st generation bioethanol as substrates for LAF. •Thin wasted bread stillage with pH control (NaOH in 4h intervals) -process productivity was improved twofold. •Added value products: •Probiotic biomass >10 9 CFU mL -1 •Animal feed – monogastric animals

4th International Conference on Sustainable Solid Waste Management, Limassol , Cyprus, 23-25 June 2016 Strategies for valorisation of wastes from bioethanol production Acknowledgem ent This work was funded by Ministry of education, science and technological development, Republic of Serbia, Project number TR 31017 Thank you for attention! Faculty of Technology and Metallurgy, University of Belgrade adjukic@tmf.bg.ac.rs